中文摘要：

目的 探讨人类胚胎期大脑额叶、脑室区（ventricular zone,VZ）/脑室下区（subventricular zone,SVZ）以及海马内星形胶质细胞的分布规律及形态特征.方法 将收集的引产胎儿按胎龄分为4组：9～11周,14～16周,22～24周和32～36周.切取额叶、VZ/SVZ和海马部位的脑组织,固定后制作冰冻切片,免疫组织化学染色后观察胶质纤维酸性蛋白（GFAP）阳性细胞的分布及形态.通过GFAP和nestin免疫荧光双标染色剔除GFAP阳性的神经干细胞.结果 ①在皮质,9～11周时GFAP阳性细胞主要位于VZ、SVZ和中间带（intermediate zone,IZ）内;14～16周时其位于VZ最内层、IZ和分子层（marginal zone,MZ）内;22～24周时皮层、髓质、IZ、SVZ和VZ最内层均有GFAP阳性细胞,髓质中的GFAP阳性细胞免疫反应强烈,胞体浓染,突起围绕胞体向四周伸展,具有典型纤维型星形胶质细胞的特征;32～36周时GFAP阳性细胞的分布模式类似于22～24周,髓质中的阳性细胞数量增加.②在海马,9～16周期间GFAP免疫反应程度较弱,主要分布在海马伞、VZ和MZ;22周后GFAP免疫反应程度增强,数量增多,分布范围逐渐扩大.③实验各组额叶VZ、SVZ以及海马的海马伞、VZ均有GFAP和nestin免疫荧光双标阳性细胞存在.结论 在人胚胎发育后期端脑星形胶质出现并逐渐增多、分布广泛并趋于成熟.

英文摘要：

Objective To investigate the distribution and morphological characteristics of astrocytes in the frontal cortex,ventricular zone （VZ）,subventricular zone （SVZ） and hippocampus in human fetuses.Methods Based on gestational age,the collected fetuses were divided into four groups：9-11 weeks,14-16 weeks,22-24 weeks and 32-36 weeks.Then the brain blocks from the frontal lobe,VZ/SVZ and hippocampus were cut out,fixed and made into frozen slices.Immunohistochemistry was used to observe the distribution and morphology of GFAP-positive cells.Furthermore,the immunofluorescence double-labeling of GFAP and nestin was used to remove GFAP-positive neural stem cells.Results ① In the frontal cortex,GFAP-positive cells were mainly located in VZ/SVZ and intermediate zone （IZ） during 9-11 weeks; the innermost part of VZ,IZ and marginal zone （MZ）at 14-16 weeks.During 22-24 weeks,GFAP-positive cells could be detected in all layers including the cortex plate,medulla,SVZ and the innermost part of VZ.The strongly immunoreactive cells,with typical morphological features of fibrous astrocyte such as intensively staining cell bodies and many slender processes,were found in the medulla.An almost same distribution pattern of GFAP-positive cells at 22-24 weeks was found during 32-36 weeks except that the number of positive cells in the medulla was greater than that at 22-24 weeks.② In the hippocampus,the weak immunoreactivity was found in fimbira,VZ and MZ during 9-16 weeks; after 22 weeks,not only the immunoreactivity became strong and the distribution range extended,but also the number of positive cells increased gradually.③ Double-labeling cells of GFAP and nestin could be detected in VZ,SVZ of the frontal cortex and VZ as well as in fimbria of the hippocampus in all groups.Conclusion During the later half of gestational age,astrocytes in human telencephalon appear and then gradually increase in number.At the same time,the astrocytes are widely distributed in the telencephalon and reach maturity in morphology progre